Is Glaucoma Genetic?

One of the most common questions I get asked is whether glaucoma is inherited. More specifically, if an individual has a glaucoma diagnosis, what is the chance his/her relatives and children also have the disease?

First, it is important to recognize that there is a clear hereditary component to the development of glaucoma. We know that the younger the individual is diagnosed with glaucoma, the higher the chance there is a direct gene which is the cause. For example, most babies who are born with congenital glaucoma have a genetic cause, and it is important for parents of a child with congenital glaucoma to discuss the implications of genetic testing with their physician.

What about adults? Studies show that if you have glaucoma, your risk of a first–degree relative also having the disease increases 5-10 times versus a non- related individual. There are now close to 30 genes which have been identified to increase risk for primary open angle glaucoma, the most common kind of adult glaucoma.

It is important to keep in mind that most adults with glaucoma do not carry a gene mutation that is the direct explanation for developing the disease. Environmental factors (ex. age, ethnic background, diabetes, high blood pressure etc.), and many of which are unknown at this point, play an important role whether the disease manifests in an individual. This means that even if two siblings both have the same risk –associated gene, one, both or neither individual may develop the disease depending on their environment. This is why the importance of early ophthalmic exams for relatives who may not have any vision complaints is so important. Many individuals do not have any symptoms until the disease has caused irreversible blindness. Early screening affords the best opportunity to assess risk and prevent damage to vision.